电动汽车HVAC模块蒸发器进风均匀性数值模拟研究

Simulation Study of Automotive HVAC Evaporator Airflow Uniformity for an Electric Vehicle

摘要: 电动汽车HVAC (Heating, Ventilation and Air Conditioning)模块是电动汽车空调系统中最为重要的部分，与乘员舱舒适性密不可分。本文针对某款电动汽车HVAC模块中气体流动、蒸发器进风均匀性等特征进行数值模拟研究。通过分析，发现该电动汽车HVAC模块的扩压段内存在偏流现象，导致蒸发器进风均匀性较差。针对该问题，本文通过改变扩压段蜗壳曲率半径R以及壳体与蒸发器进口截面之间的角度θ，分为三种方案，研究在典型模式下这两种参数变化对HVAC模块内部气体流动及蒸发器进风均匀性等特征的影响。发现从case 1变化到case 2的过程中，蒸发器进风均匀性得到明显改善，蒸发器的有效利用面积也逐渐增大，而在case 3方案中，蒸发器的进风均匀性再次变差，蒸发器有效利用面积再次减小。

Abstract: The HVAC module is the most important part of air conditioning system in an electric vehicle, the design of which strongly influents the passenger cabin comfort. In this paper, the simulation study of air flow, air distribution and airflow uniformity of evaporator in an HVAC of an electric vehicle is carried out. Through simulation analysis, it is found that there is a drift phenomenon in the inlet air expansion section of the HVAC, resulting in airflow uniformity of the evaporator. This paper divides the radius of curvature R of the expansion section and the angle θ between the shell and the evaporator into three cases. The influence on the airflow uniformity of the evaporator is studied in three types. It is found that from case 1 to case 2, the airflow uniformity of the evaporator is significantly improved, and the effective utilization area of the evaporator is gradually increased. While from case 2 to case 3 solution, the airflow uniformity of the evaporator is again deteriorated, the effective use area is reduced.